Internal combustion engine



' C. E. SUMMERS INTERNAL COMBUSTION ENGINE June 28, 1955 s Sheets-Sheet 1 Filed Dec. 16, 1953 Inventor By I 2; W Attorneys June 28, 1955 c. E. SUMMERS INTERNAL-COMBUSTION ENGINE Filed Dec. 16, 1953 3 Sheets-Sheet 2 I (2&1522232 Attorneys June 28, 1955 c. E. SUMMERS 2,711,723

INTERNAL COMBUSTION ENGINE Filed Dec. 16, 1953 3 Sheets-Sheet 3 United States Pate-m INTERNAL CQIWBUSTION ENGINE Caleb E. Summers, Orchard Lake, Mich.

Application December 16, 1953, Serial No. 398,511 in Claims. (21. 123-191) This invention relates to improvements in internal combustion engines particularly as disclosed and claimed in prior Patents 1,568,638 granted January 5, 1926., and 1,833,445 granted November 24, 1931, in the name of this applicant.

Fuel and air mixtures in which the fuel is thoroughly vaporized and the mixture homogeneous, explode effectively where the ratio of fuel to air by weight is as low as l to 20. However, a number of causes combine to make the mixture required by conventional engines much richer. Since a certain minimum ratio fuel mixture is required'at the spark plug for ignition, the leanest mixture in the combustion chamber of the cylinder having the leanest mixture, must be rich enough to burn rapidly enough for ignition purposes under all conditions causing variation in metering and vaporization of the fuel employed in the mixture. Under such circumstances all variations in homogeneity of the mixture, distribution to the cylinders, degree of vaporization, and carburetor metering characteristics must be added, to provide a richer mixture. To make an engine that will be operable under all conditions,'a mixture ratio of about 1 pound of fuel to 13 pounds of air, therefore, is required. If the mixture is made leaner than this, certain cylinders under certain conditions may fail to fire, which will result not only in poor operation but in actual loss in fuel ecomony. A richer mixture, therefore, is provided to prevent such loss. It will be apparent, therefore, that the practical operation of a conventional engine fuel system is obtained only by a sacrifice in economy equal to at least 30% of what it might be under other conditions.

It is now proposed to provide means by which an engine can be operated at all times at its maximum fuel economy. In doing this, it is proposed to compensate for variations in metering and distribution in such a way that these variations will result in a mixture that is at times leaner than is now required in conventional engines. Under such circumstances, the richest mixture delivered to any cylinder under the richest metering conditions will have an ideal mixture ratio at all times and all variables from this will be toward a leaner mixture ratio. To accomplish such purposes, it is proposed to provide means capable of igniting lean-mixtures which would not otherwise be readily ignited by the sparkignition means of an engine. g

The prior patents referred to disclose auxiliary ignition or firing chambers forming a part .of the combustion chambers of the engines disclosed. These ignition or firing chambers are provided with spark plugs or other ignition devices to fire charges supplied to the firing chambers through valves in addition to the intake valves of the engine. These patented structures have been complicated by special mechanisms required to operate the additional valves employed in the firing chambers. These structures also have had the disadvantages resulting from the location of the spark plug in places where the combustible mixture may be leaner than is required for good ignition. These and other features have resulted in engine performance that is not equal to be standard of performance resulting from utilizing the principles involved in the present invention.

According to the present invention the ignition of the charge in firing chambers which communicate with and 2,711,723 Patented .Iune 28, 1955 ice - though not necessarily retained and provision is made for simplification and improvement in operation by employinga number of other features which may be used singly or in combination as desired. One of these features involves dispensing with the valves which heretofore have been employed in firing chambers of this kind and providing nozzles adjacent each inlet valve of the engine. These nozzles are employed in supplying a relatively rich and separate combustible mixture to each combustion chamber, and in directing this separate charge to the ignition chamber if one is employed or to the part of the combustion chamber in which the ignition device or spark plug is employed. The nozzles are located ad jacent the inlet valve for each cylinder and are timed. to supply the rich combustible mixture whenever the.

inlet valve for the cylinder is opened. The nozzles may be supplied with a combustible mixture of fuel and air through a rich mixture supply conduit which is connected to the carburetor and which supplies the fuel and air mix-. ture to a mixture distributor valve or device from which branch pipes lead to the nozzles adjacent the valves in the respective cylinders. The mixture distributor device may be in the form of a rotary valve which may be driven at the speed of the camshaft of the engine. The ignition or firing chamber which may be employed in each cylinderis provided with an outlet passage which communicates with the clearance chamber part of the combustion chamber may be directly opposite the end of the piston. The firing chamber preferably is of cylindrical form with the axis arranged in parallel relation to the axis of the cylinder of the engine. The connecting passage preferably is arranged in tangential relation to the firing chamber so that on the compression stroke of the engine the charge will be rotated in the firing chamber to provide a vortex of turbulent fluid of greater density adjacent the periphery than adjacent the axis or central part of the vortex. It is desirable to locate the spark plug so that the spark will be near the edge of the vortex of.

turbulent fluid and near the entrance to but at one side of the connecting passage leading from the ignition cham-.

her to the clearance chamber part of the combustion chamber. In such position the spark plug terminals and the spark gap will be shielded from the flow of lean mixture into the ignition chamber during and near the end of the compression stroke of the engine. It is also desirable to locate the ignition or firing chamber, the connecting passage and the clearance chamber parts of the combustion chamber in a position to be intersected by a single plane. Under such circumstances, the ignited charge in the ignition chamber will be projected as a jet or'blast, from the connecting chamber and diametrically across the clearance chamber part of the combustion chamber without directly impinging upon any wall until the blast reaches the opposite side of the clearance chamber. this primary blast or explosion which originates in the ignition chamber and near the end of the connecting pas-' sage leading to the clearance chamber, projects the flame diametrically across the combustion chamber and from which location the flame forming the blast burns in both directions towards the sides of the clearance chamber. This torch like flame extending across the clearance chamber will readily ignite and burn the relatively lean mixture forming the greater part of the fluid supplied to the cylinder at less than full load positions of the throttle. At full load positions of the throttle the carburetor de livers a full power mixture to the engine. a In the drawings: Figure 1 is a side elevational view of an engine embracing the principles of the invention and illustrating particularly the intake and exhaust systems of the engine.

The igniting, heating and pressure raising effect of V Figure 2 is a fragmentary plan view of the engine structure illustrated by Figure 1.

Figure 3 is a fragmentary cross sectional view of the engine disclosed by Figures 1 and 2. Figure 3 is taken in a vertical plane through the inlet valve, firing chamber, spark plug, connecting passage and clearance chamber of one or" the cylinders of the engine and substantially in the plane of line 33 on Figure 2, looking in the direc' tion of the arrows thereon.

Figure 4 is a horizontal sectional view through a distributor valve employed in the engine disclosed by the preceding figures. Figure 4 is taken substantially in the plane of line 44 on Figure 5, looking in the direction of the arrows thereon.

Figure 5 is a fragmentary vertical sectional view of the engine disclosed by the preceding figures and showing the distributor valve driving mechanism employed. Figure 5 is taken substantially in the plane of line 5-5 on Figure 2, looking in the direction of the arrows thereon.

Figure 6 is a fragmentary bottom plan view of the head of the engine and showing the clearance chamber, the firing chamber and the connecting passage formed in the head of one of the cylinders of the engine. Figure 6 is taken in the plane of line 6-6 on Figure 1 looking in the direction of the arrows thereon.

Figure 7 is a vertical sectional view through a rich mixture supply device forming a part of the charge forming device employed in supplying a relatively rich fuel and air mixture to the engine. Figure 7 is taken substantially in the plane of line 77 on Figure 2 looking in the direction of the arrows thereon.

Figure 8 is a transverse sectional view through the rich mixture supply device and a part of the float bowl of the carburetor to which it is attached. Figure 8 is taken substantially in the plane of line 88 on Figure 2 looking in the direction of the arrows thereon.

The engine 10 employed in practicing the invention comprises an engine block 11 in which a plurality of aligned cylinders 12 are formed. The cylinders 12 contain pistons 13 that reciprocate therein in response to the operation of the engine crankshaft. The open upper ends of the cylinders 12 are closed by an engine head 14 which is secured thereto by bolts 16. Each cylinder 12 has inlet and exhaust valves reciprocably mounted in the block 11 and adapted to be operated by a cam shaft 78 also driven by the crankshaft of the engine. One of the inlet valves of the engine is indicated at 17 in Figure 3.

Each cylinder 12 of the engine is formed to provide a combustion chamber 18 which consists essentially of a clearance space or chamber 19, a firing or ignition chamber 21 and a connecting passage 22 extending between the firing chamber 21 and the clearance chamber 19. In the present instance, the various parts of the combustion chamber are formed in the engine head 14, the clearance chamber 19 being adapted to extend to any desired extent across the end of the piston 12, the inlet valve 17v and the exhaust valve positioned at one side of the inlet valve 17. Except for the presence of the gasket 20 on which the head 14 is secured to the block 11 the lower wall of the head 14 would be in the plane of the upper wall of each of the pistons 13 when the pistons 13 are in their upper dead center positions within the cylinders 12. The clearance chamber 19 projects upwardly Within the lower wall of the head 14 in such manner as to provide a clearance space by which the exhaust gas and combustible mixture may flow to and from the cylinders through the inlet and exhaust valves. The firing chamber 21 also projects into the lower wall of the head 14 in a region beyond the inlet valve for each cylinder and beyond the clearance chamber 19. The lower end of the firing chamber 21 is closed by the upper wall of the block 11. The communicating passage 22 extends between the firing and clearance chambers 21 and 19 respectively in a region below the upper extremity of the firing chamber 21. The communicating passage 22 is so located and directed as to be parallel to a horizontal plane which extends approximately through the middle of the firing chamber 21 and the clearance chamber 19.

The firing chamber 21 is formed in the head 14 preferably by a cylindrical opening 23 having a tapering upper end indicated at 24. The axis of the cylindrical opening 23 and the tapering end 24 is substantially parallel to the axis of the cylinder 12. Figure 6 illustrates the relative position of the various parts of the combustion chamber with respect to the cylinder and the valves for each cylinder. In Figure 6 the position of the cylinder 12 is illustrated partly by the dot-and-dash line indicated by the numeral 12 and partly by the semi-circular end of the clearance chamber 19. It will be apparent from Figure 6 that the cylinder 12 communicates with one end of the clearance chamber 19 directly opposite the piston in the cylinder, and at the opposite end one side 26 of the clearance chamber is disposed over the exhaust valve and the other side 27 is disposed over the inlet valve for the cylinder. The firing chamber 21 projects into the head 11 adjacent the side 27 of the end of the clearance chamber 19 containing the inlet valve 17. The communicating passage 22 is disposed in tangential relation to the cylindrical part 23 of the firing chamber 21 and below the conical end 24. The axis of the communicating passage 22 projects in a direction diametrically across the clearance space 19 and intersects the opposite end wall of the clearance chamber 19 which in the present instance is coincident with an opposite wall of the cylinder 12.

A spark plug 28 is provided for each cylinder of the engine 10. The spark plug for each cylinder is threaded in an opening the axis of which is disposed obliquely to the axis of the firing chamber 21 and which communicates with the side of the tapering end 24 adjacent the end of the passage 22. The spark gap between the terminals 29 of the spark plug is adjacent the end of the passage 22 and within the tapering end 24 of the firing chamber 21.

It will be apparent from the foregoing that when fluid from the cylinder 12 is compressed through the passage 22 and into the firing chamber 21 the fluid will be rotated rapidly. Such rapid rotation of the fluid within the chamber 21 will tend to form a vortex around the axis of the chamber 21 and within which the heavier particles of fuel will accumulate adjacent the periphery of the chamber. Since the terminals 29 of the spark plug 28 are adjacent the periphery of the firing chamber 21 it will be apparent that the spark gap between the terminals will be within the richest part or the part of greatest density of the fuel mixture being compressed within the chamber 21 and through the passage 22. Being within the most dense part of the charge compressed into the firing chamber 21 it will be apparent that the spark plug will readily ignite a mixture much leaner than could be ignited in the chamber were the passage 22 not connected in such a way as to form the vortex of fluid within the chamber. When the whirling fluid vortex is ignited in the firing chamber 21 it will be apparent that ignition will occur first adjacent the periphery of the vortex which communicates with the opening leading to the passage 22. A blast of burning fluid therefore will be shot from the passage 22 in the direction indicated by the arrows on Figure 6, toward the opposite end of the clearance chamber 19 and diametrically across approximately the middle of the clearance chamber 19. The ignited blast carried by the pressure wave resulting from the explosion in the chamber 21 will reach the opposite end wall of the clearance chamber 19 in a much shorter time than would be the rate of flame travel across the clearance chamber 19. The fluid in the chamber 19 will then burn transversely across the clearance chamber 19 on a flame front twice the length of the distance traveled by the blast and moving toward the opposite side walls of the chamber. Assuming the part of the vortex containing the most dense part of the mixture in the firing chamber 21 to be rich enough to be readily ignited by the spark plug, thenv it will be apparent that the flaming blast of fluid projected across the clearance chamber 19 will burn a mixture in the chamber 19 much leaner than could be ignited by the terminals of a spark plug if directly employed to ignite such a mixture.

It is proposed to supply combustible mixtures to each of the cylinders of the engine through intake passages indicated at 31. These intake passages 31 terminate in intake ports 32 which are opened and closed by the inlet valves 17 of the engines. The intake passages 31 communicate with branches 33 leading from a main distribution passage 34 of an engine inlet manifold indicated at 36. The manifold 36 has a mixture supply passage 37 to the upper end of which a carburetor 38 is secured by bolts 39. The carburetor 38 has an induction passage 41 controlled by choke valve 42 and throttle valve 43 which are operated in any suitable manner by operating levers indicated at 44 and 46 respectively. The induction passage 41 in the region between the choke valve 42 and throttle valve 43 has the usual venturi and main fuel supply jet where a primary or main fuel supply mixture for operating the engine is formed. Fuel for such purposes is supplied to the main fuel supply jet by a float chamber indicated at 45.

A characteristic of carburetors of this kind is that the charge formed by the main fuel supply jet is too lean to properly operate the engine in part throttle positions when a proper mixture for operating the engine at wide open throttle positions is provided. It has been the practice therefore to provide various auxiliary or idling jets to further enrich the entire mixture to operate the engine at all part throttle positions. For example, at idling position a large amount of auxiliary fuel is supplied to enrich the entire mixture and this auxiliary supply of fuel is decreased as the throttle moves toward open position.

Instead of enriching all of the mixture in this manner it is proposed merely to form a small amount of secondary mixture which is rich enough to ignite at the compression ratios prevalent at less than wide open throttle positions and then to supply this mixture directly to the firing chambers 21. It is proposed to supply this small amount of rich secondary mixture to the engine through the mixture supply nozzles indicated at 47. One of the mixture supply nozzles 47 is provided for each of the cylinders of the engine and each nozzle is secured in such way that the inner end thereof projects through a wall of the block 11 and into one of the inlet passages 31. The nozzles 47 have obliquely disposed outlet passages or jets 48 which are directed toward the ends of the connecting passages 22 which communicate with the clearance chambers 19. The ends of the nozzles 47 are located below the inlet valves 17 so that the passages 48 may discharge into the connecting passages 22 when the valves 17 are open. Supply passages 49 within the nozzles 47 communicate externally of-the block 11 with conduits 51 for each of the cylinders of the engine. The conduits 51 are connected to the passages within the nozzles 47 by terminal blocks 52 which are secured to the ends of the nozzles 47 and the block 11 by screws 53. The opposite endsof the conduits 51 communicate with ports 54 in the body 56 of a secondary mixture distributor Valve indicated generally by the numeral 57. The ports 54 are arranged in a plane in the body 56 in radially disposed relation to one another and about the axis of a conical opening 58 projecting into the valve body from the lower surface thereof. The inner ends of the ports 54 are equally spaced with respect to one another, there being one port for each of the cylinders of the engine 10. Projecting into the conical opening 58 is a cone shaped valve member 59 having an axially disposed opening or distribution chamber 61 formed adjacent the upper end thereof. The lower end of the valve member 59 has an opening therein which is adapted to receive the upper end of an operating rod indicated at 63. The upper end of the rod 63 is provided with a tongue 62 which projects into a slot in the member 59 to provide for the rotation of the valve member 59 by the rod 63. The lower end of the rod 63 extends into the upper end of a tube 64 having a pin 66 projecting transversely thereacross and through an elongated opening 67 formed in the part of the rod 63 within the tube 64. The opposite end of the tube 64 receives a rod 68 which is secured thereto by a pin 69. Spring 71 is disposed in the tube 64 between the ends of the rods 63 and 68. It will be apparent that the spring 71 will resiliently hold the valve member 59 in operative relation to the surface forming the conical opening 58 in the lower part of the valve body 56. The rods 63 and 68 and the tube 64 extend downwardly from the distributor 57 through a vertically disposed slot 72 which is formed" in the adjacent wall of the block 11. The lower end of the rod 68 extends through an opening in the wall of the block 11 and is keyed by a pin 73 in an axial opening formed in the upper end of a short shaft indicated at 74. The opposite ends of the shaft 74 are journaled in openings formed above and below a transversely disposed slot 76 formed in a bearing block indicated at 77. The block 77 is secured in an opening formed in the block 11 in directly opposed relation to the middle part of the camshaft 78 of the engine. The slot 76 in the block 77 is adapted to receive a worm wheel 79 which is mounted on the shaft 74 in such manner as to rotate within the slot 76. The teeth of the worm wheel 79 are adapted to be operatively driven by the Worm gear 81 secured rigidly upon an adjacent part of the camshaft 78. The worm gears 79 and 81 drive the valve member 59 at camshaft speed through the drive shaft 82 which consists of the various shafts 63, 68, 74 and the tube 64. A rotary seal 83 consisting of a pair of concentric tubes 84 and 86 secured to the shaft 68 and the front wall of the block 11 within the opening through which the shaft 68 extends, prevents the passage of dirt and water into the crankcase of the engine through the opening for the shaft 82.

The opening or distributing chamber 61 which is formed in the upper end of the valve member 59 has a single port 87 which extends radially therein in a position to successively communicate with the ports 54 gformed radially about the valve member 59 and in the block 56. The valve. member 59 and the inlet and exhaust valves of the engine are relatively timed in such a way that the port 87 successively communicates with the passages or ports 54 at about the same time the inlet zvalves for the engine are successively opened. The conduits 51 are connected with the nozzles 47 to agree with the firing order of the engine cylinders. Each inlet valve therefore will open at about the time the port 87 communicates with the port 54 for the conduit 51 leading 3 to the nozzle 47 for the cylinder the inlet valve of which is commencing to open. A rich secondary or auxiliary mixture of fuel and air is supplied to the distributing chamber 61 by a conduit 88 the end of which is secured in an opening in the upper wall of the block 56. The

conduit 88 leads from an auxiliary or secondary fuel larly by Figures 7 and 8.

and air mixing device 89 which is secured to the side of the float chamber and forms a part of the carburetor 38.

The auxiliary mixing device 89 is illustrated particu- The device 89 comprises a block 91 which is adapted to be secured to the carburetor float chamber 45 by bolts 92. The block 91 contains a vertically disposed mixing passage or chamber 93, the upper end of which is connected to conduits indicated at 94 and 96. The conduit 94 may be connected through a suitable metering device 97 to the induction passage of the carburetor on the inlet side of the throttle while the conduit 96 may be connected through a suitable metering device 98 to the induction passage of the carburetor on the engine side of the throttle. The lower end of the mixing passage 93 is connected to the auxiliary mixture supply conduit 88 leading to the distribution chamber 61 in the distributor valve 57.

Fuel may be supplied to the mixing chamber 93 through a small passage or jet 99 which communicates with the mixing chamber between the upper and lower extremities thereof and above the fuel level in the float chamber 45. The passage 99 is connected to the interior of the float chamber 45 by a passage 101 formed in the block 91 and the lower end of which is intersected by a passage containing a needle valve 102. The valve 102 controls an orifice 103 communicating with an opening 104 in the side wall of the float chamber 45 a considerable distance below the liquid fuel level in the float chamber. The needle valve 102 may be screw threaded into the opening in the block 91 as is indicated at 106 and the opening leading to a slot in the end of the screw threaded part 106 may be closed by a screw indicated at 107.

It will be apparent that the conduits 94 and 96 will subject the mixing chamber 93 to a depression in pressure which will increase as the throttle is closed and which will decrease as the throttle is opened. This variable depression in pressure in the mixing chamber 93 will cause fuel to flow into the mixing chamber 93 through the orifice 99 at a rate varying inversely with the extent of the through opening. The conduits 94 and 96 not only will create a depression in pressure in the mixing chamber 93 but the conduit 94 also will admit a metered supply of air into the mixing chamber 93 which will vary inversely as the opening of the throttle. lt will be apparent therefore that both air and fuel will be admitted to the mixing chamber 93 at a rate inversely proportional to the opening of the engine throttle. The air and fuel so admitted will form a rich mixture in the mixing chamber 93 which may be exhausted from the mixing chamber 93 through the conduit 88 leading to the distributor valve 57.

The opening of the inlet valves 17 of the engine in timed relation to the operation of the distributor valve 57 will subject the nozzles 47 adjacent each inlet valve 17 to the depression in pressure in the cylinders which will occur on the suction stroke of the piston in each cylinder. The depression in pressure in the cylinders alfecting the nozzles 47 will cause the rich fuel mixture formed in the mixing chamber 93 to be projected from the passages 48, through the inlet valves and toward the ends of the connecting passages 22, in timed relation to the opening of the inlet valves. Simultaneously with the projection of the rich mixtures from the openings 48 in the nozzles 47 the main supply of fuel and air forming a relatively leaner mixture will be admitted to the cylinders through the fuel supply passages 31 and the inlet valves 17. When the suction stroke in any cylinder of the engine is completed it will be apparent that the cylinder will be filled with a small quantity of a relatively rich mixture and a large quantity of a relatively lean mixture. The richer mixture will be in the vicinity of the connecting passage 22 leading to the firing chamber 21. The leaner mixture will fill the remaining parts of the cylinder and the clearance chamber l9 adjacent the connecting passage 22. On the compression stroke of the piston it will be apparent that the richer mixture supply will be tangently compressed into the firing chamber 21 to form a whirling vortex of fluid the density of which will increase toward the peripheral surface of the firing chamber. As the piston continues to move on the compression stroke of the engine the leaner mixture filling the larger part of the combustion chamber also will be compressed into the firing chamber 21 through the connecting passage 22. However, the richer mixture having first been admitted to the firing chamber will be compressed toward the ends of the firing chamber and in one end of which the spark plug. 28 is located. Toward the end of the compression stroke when the spark jumps the gap between the terminals 29 of the spark plug the richer part of the mixture will be whirling across the terminals of the spark plug and will be quickly ignited at the periphery of the firing chamber and adjacent the open end of the connecting passage 22. \Vhen the rich mixture is so ignited the contents of the firing chamber will be discharged as a burning jet or blast which will be projected diametrically across the clearance chamber 19. Thereafter the leaner mixture largely filling the chamber 19 will quickly burn in two directions along a flame front twice the length of the distance between the end of the connecting passage 22 and the opposite end of the clearance chamber 19. Under such circumstances it will be apparent that the leaner mixture in the clearance chamber 19 will burn rapidly toward the opposite side walls of the clearance chamber 19 even though the main part of the mixture filling the clearance chamber 19 may be so loan that it could not be ignited in the time available by the terminals of a spark plug.

lf desired, the supply passage 37 leading to the main distribution passage 34 of the inlet manifold 36 may be heated at a rate which is inversely proportional to the throttle opening. This may be done by the use of any suitable manifold heating device or vaporizer such as that shown by Jack No. 1,651,393, granted December 6, 1927. in such a vaporizing device a valve is employed which directs the mixture at part load through a high temperature vaporizer formed by a part of the exhaust manifold by which the products of combustion are exhausted from the engine. At full load position of the throttle the valve is closed thereby permitting the mixture to flow directly to the engine without heating. In the present instance the vaporizer may be located at a junction between the supply passage 37 for the inlet manifold 36 and the outlet passage 109 leading from the exhaust manifold 110 of the engine it). The exhaust manifold 110 has branch passages 111 which are connected to the exhaust valves of the engine through exhaust passages not shown.

It is not necessary at low throttle positions to completely fill the combustion chamber in the cylinder of any engine with an over-rich mixture suitable for ignition under all circumstances by the terminals of a spark plug. It is only necessary to provide a small quantity of such mixture and to confine such mixture to the vicinity of the terminals of the spark plug of the cylinder. When this quantity of mixture is ignited, then the heated gases resulting therefrom may be employed in igniting the much leaner mixture with which the remaining parts of the combustion chamber of the cylinder may be filled. The depression in the mixing chamber 93 caused by the extent of the throttle opening in the main induction passage of the carburetor 38 will cause the rich mixture supplied to the cylinders by the nozzles 47 to decrease as the throttle opening increases. However, the richness of the mixture in the main induction passages leading from the carburetor 38 will increase as the throttle opens due to the increase in the depression in the induction passage caused by the increased rate of flow of air in the induction passage. At low throttle opening positions the fuel mixture adjacent the spark plug in a cylinder of the engine will ignite in the small amount of rich mixture which is supplied to the firing chambers 21 by the nozzles 47. As the quantity of the rich mixture decreases with the opening of the throttle the richness of the main mixture will increase until at fully open throttle the mixture supplied by the main induction passage of the carburetor will be readily ignitable by the spark plugs of the engine.

In the claims:

1. An internal combustion engine comprising a cylinder having a combustion chamber, an intake valve for controlling the fiow of combustible mixture to said combustion chamber, an ignition chamber forming a part of said combustion chamber and being located adjacent said intake valve, a clearance chamber forming another part of said combustion chamber and being formed in part at the end of said cylinder, means controlled by said intake valve for supplying a relatively rich combustible mixture to said ignition chamber, means controlled by said intake valve for supplying a relatively leaner combustible mixture to said clearance chamber, and means for igniting said relatively rich combustible mixture in said ignition chamber.

2. An internal combustion engine comprising a cylinder having a combustion chamber formed by a clearance chamber at the end of the cylinder and by an ignition chamber at one side of the cylinder and by a connecting passage between the ignition chamber and the clearance chamber, said ignition chamber being of circular contour and having said connecting passage arranged in tangential relation thereto, said connecting passage at the end thereof communicating with said clearance chamber being directed at the opposite end wall of said clearance chamber along a line within and intermediate the side walls of said clearance chamber, means for supplying a combustible charge to said combustion chamber and means for igniting said charge in said ignition chamber, said igniting means being arranged to ignite the charge in said ignition chamber adjacent the periphery of said ignition chamber and adjacent the end of said connecting passage communicating with said ignition chamber.

3. An engine comprising a cylinder having a reciprocal piston therein and a head for closing one end of said cylinder, an intake valve for supplying combustible mixture to said cylinder, a clearance chamber formed in the head of said cylinder and at the end of said piston, a firing chamber adjacent said clearance chamber, and a connecting passage between said firing chamber and said clearance chamber, said connecting pasasge being tangently disposed with respect to said firing chamber and having an end communicating with said clearance chamber at one end of said clearance chamber and directed across said clearance chamber toward the end wall at the opposite end of said clearance chamber, means for supplying a relatively rich fuel and air mixture to said firing chamber, and means for supplying a relatively leaner fuel and air mixture to said clearance chamber through said inlet valve.

4. An internal combustion engine comprising a cylinder having a reciprocal piston therein and a head closing one end thereof, an intake valve for said cylinder, a clearance chamber formed in said head and communicating with the end of said cylinder, said intake valve being operatively positioned to open into said clearance chamber for supplying combustible mixture to said clear ance chamber, a firing chamber formed in said head at one side of said clearance chamber, said head being formed to provide a communicating passage between said chambers and having an end connected to said clearance chamber and directed across said clearance chamber toward the opposite side of said clearance chamber and having the opposite end of said connecting passage disposed in tangential relation to said firing chamber, said firing chamber being formed to provide an end extending to one side of said connecting passage, and an igniting device in said end of said firing chamber and having a spark gap between the terminals thereof, said spark gap being positioned adjacent the periphery of said firing chamber and near the end of said connecting passage and out of the path of movement of combustible mixture compressed into said firing chamber through said connecting passage upon the compression stroke of the piston in said cylinder.

5. An engine as defined by claim 4 and in which means is provided for supplying different combustible mixtures to said clearance chamber through said inlet valve, one of said combustible mixtures being directed by said means inwardly through said inlet valve and toward the end of said connecting passage leading to said firing chamher.

6. An engine comprising a cylinder having a reciprocal piston therein and an inlet valve, a clearance chamber formed in the head of said cylinder, an inlet passage lead ing to said clearance chamber and controlled by said inlet valve, a firing chamber at one side of said clearance chamber and adjacent said valve and having a tangentially disposed connecting passage through which said firing chamber communicates with said clearance chamber, passage means for supplying a combustible mixture through said inlet valve to said clearance chamber, nozzle means in said passage means and controlled by said inlet valve and having a discharge passage formed at the end thereof and directed through the opening provided by said inlet valve and toward said connecting passage leading to said firing chamber, and means for igniting the combustible mixture compressed into said firing chamber.

7. An engine comprising a plurality of cylinders having an intake valve for each cylinder and a clearance chamber formed in the head of each cylinder, means for supplying combustible mixtures to said clearance chambers through said intake valves, a firing chamber formed in the head for each of said cylinders and located at one side of the clearance chamber and adjacent the inlet valve for each of said cylinders, a connecting passage for each of said cylinders formed between said firing and clearance chambers for each of said cylinders, and nozzle means associated with each of said intake valves and having a discharge passage directed through the intake valve for each cylinder and toward said connecting passage leading to the firing chamber for each cylinder, a distributor valve controlling the discharge of combustible mixture through said nozzles, and means for operating said distributor valves in timed relation to the operation of the inlet valves for said cylinders.

8. An internal combustion engine comprising a plurality of cylinders each having an inlet valve controlling the supply of combustible mixture to said cylinders, an injector nozzle for each cylinder and being provided with a discharge passage directed through the opening provided by the inlet valve for each cylinder, a plurality of conduits for supplying combustible mixture to said injector nozzles, a distributor valve connected to all of said conduits for supplying combustible mixture to said conduits, said conduits being connected to said nozzles in timed relation to the operation of the intake valves for said engine, and means forming a combustible mixture and supplying said combustible mixture to said distributor valve.

9. An internal combustion engine comprising a cylinder having a piston and a head for closing the cylinder, an inlet valve controlling all of the fuel and air supplied to said cylinder, a clearance space formed between said head and saidpiston and having a firing chamber formed at one end thereof adjacent said inlet valve, a spark plug in said firing chamber adjacent one edge of said inlet valve and in directly opposed relation to the opening at said edge of said inlet valve when said inlet valve opens, and passage means for supplying fuel and air to said cylinder through said inlet valve, said passage means including means for directing a greater proportion of the fuel supplied by said passage means in the vicinity of said spark plug in said firing chamber than elsewhere in said cylinder.

10. An internal combustion engine as defined by claim 9 and in which said passage means includes a nozzle having an outlet orifice directed toward said spark plug for directing a greater proportion of the fuel supplied by said passage means in the vicinity of said spark plug than elsewhere in said cylinder.

References Cited in the file of this patent UNITED STATES PATENTS 1,069,502 Wadsworth Aug. 5, 1913 1,712,465 Woolson May 7, 1920 1,802,848 Summers Apr. 28, 1931 1,948,825 Perrine Feb. 27, 1934 2,314,175 Summers Mar. 16, 1943 

